In this chapter, "insurer" means an insurance company, reciprocal or interinsurance exchange, mutual insurance company, farm mutual insurance company, capital stock insurance company, county mutual insurance company, Lloyd's plan, surplus lines insurer, or other legal entity engaged in the business of insurance in this state. The term includes:
(1) an affiliate described by Section 823.003(a);
(2) the Texas Windstorm Insurance Association established under Chapter 2210;
(3) the FAIR Plan Association established under Chapter 2211; and
(4) the Texas Automobile Insurance Plan Association established under Chapter 2151.